Best answer! Charge out the ***. River Rock is tough to move and spread like he said! Theyre your family yeah but 1/3 way through your gonna be punching yourself! I just finished a river rock job yesterday , 460ft of vinyl fence 6" off each side. Although it paid well, IT SUCKED!!! I think I made my mind up not to take on those rock jobs anymore, and If I do, Ill Charge an obsured amount and theyd be stupid to accept. Best Of Luck!!!